Now that everyone and their mother's got a smartphone, you've got a pile of sweaty capitalists pounding on the door trying to find every last conceivable way to turn the trend into cold, hard cash. One of the most obvious -- quality apps from a central clearinghouse -- is proving fruitful through countless official platform app stores, but targeted mobile advertising has to be a close second. Google saw the writing on the wall and snapped up AdMob not long ago; one of AdMob's competitors, Quattro Wireless, is now rumored to be locked up for a purchase by Apple for a cool $275 million as early as tomorrow. While mobile ads (or ads of any sort, really) aren't event remotely in Cupertino's repertoire, it's easy to see how this could give the company an opportunity to ca